- From: Khalid Belhajjame <Khalid.Belhajjame@cs.man.ac.uk>
- Date: Thu, 03 May 2012 14:02:47 +0100
- To: Jun Zhao <jun.zhao@zoo.ox.ac.uk>
- CC: Stian Soiland-Reyes <soiland-reyes@cs.manchester.ac.uk>, public-prov-wg@w3.org
On 03/05/2012 12:42, Jun Zhao wrote: > > Stian, >>> I am confused. Are you talking about wasStartedByActivity or >>> wasInformedBy? >>> I guess you are talking about wasStartedByActivity. And I think this is >>> precisely why Tim is also pushing to keep only one of them in the DM. > > Good try! >> >> A wasInformedBy B says that B used X, wasGeneratedBy A. If we also >> know entity X and how it was used and generated, wasInformedBy is just >> restating that. > > Do you mean to say that > > A wasInformedBy B --> > > there is an X that wasGeneratedBy B, and used by A That what I understood too. I suggest to make X explicit, as opposed to leave it unspecified as the definition of wasInformedBy in the DM suggests. >> >> A wasStartedByActivity B says that B wasStartedBy X, which >> wasGeneratedBy A. If we also know that entity X and how it started A >> and was generated by B, then wasStartedByActivity is just restating >> that. > > A wasStartedByActivity B -> > > A wasStartedBy X, which wasGeneratedBy B > > Although my understanding is that wasStartedByActivity was not meant > as a shortcut, but for cases where X is truly unknown, for expressing > control-flow relationship between activities. This is the 'hidden > trigger' case that Tim said that he might have missed. The example of workflow triggering a subworkflow uses this hidden trigger. Here is an example that actually specify the entity (or trigger) more explicit. :letterRespection a prov:Activity . :accidentNotification a prov:Entity . :accidentNotification prov:wasGeneratedBy :letterReception . :insurranceClaim a prov:Activity ; prov:wasStartedBy :accidentNotification ; prov:wasStartedByActivity :letterReception . Notice that :insurranceClaim does not use :accidentNotification, and therefore :insurranceClaim was not informed by :letterReception. khalid > > > cheers, > > Jun >> >> >> So both are shortcuts, and should have value as such where we don't >> know much about X, or where we add more data to that indirect >> relationship. >> >> > > >
Received on Thursday, 3 May 2012 13:03:17 UTC